(1) Field of the Invention
This invention relates to hydrometallurgy and more specifically to supplying, separating and assorting solids in liquid suspension by a vertical current.
(2) Description of the Prior Art
PACE, U.S. Pat. No. 3,863,002, states,
"Presently uranium ores are leached two ways: one is an agitated leach, the other is a static leach. In the case of the agitated leaching, large volumes of lixiviant are required to do the leaching and a liquid-solid separation step must be used before the uranium can be recovered from the lixiviant. The disadvantages of this system are the large volumes required for leaching, power cost for agitation, high equipment cost for solid-solution separation and excessive dilution of lixiviant after uranium dissolution resulting in a solution low in uranium concentration and low in acid content. If the lixiviant were not excessively diluted during the liquid-solid separation step, a large portion of the acid in this solution could be used again. PA1 "In the case of present static leaching operations, two methods are used: one is to introduce the lixiviant to the top of a heap of raw ore and allow the lixivant to perculate through the ore, and the other is to introduce an acid solution with a low concentration of sulfuric acid on top of a heap of ore that has been previously mixed with a solution with a very high acid concentration. There are some problems with this type of leaching, the flow rate is usually extremely low, and there is a great possibility that all the acid will not make good contact with the lixiviant." PA1 Ekstrom, U.S. Pat. No. 2,960,226 PA1 Meyer, U.S. Pat. No. 3,250,589 PA1 Mitterer, U.S. Pat. No. 3,777,003 PA1 Smith, U.S. Pat. No. 3,808,306 PA1 Robinson, U.S. Pat. No. 3,885,017 PA1 Kurata, U.S. Pat. No. 3,929,963 PA1 1. Decrease in sampling cost. PA1 2. Elimination of fine ore storage surge capacity. PA1 3. Decrease in crushing cost. PA1 4. Complete elimination of leaching agitators. PA1 5. Complete elimination of sand-slime separation equipment. PA1 6. Complete elimination of thickners, settlers or liquid clarification. PA1 7. Eighty percent reduction in capital cost. PA1 8. Eighty-five percent reduction in labor cost. PA1 9. Eighty percent reduction in water requirements. PA1 10. Fifty percent reduction in heating requirements.
McKNIGHT, U.S. Pat. No. 3,224,581, discloses a process wherein ore is placed in the middle tank. Water is forced through a screen under the ore so the ore reaches a teeter condition and, therefore, is classified. LAUGHLIN, U.S. Pat. No. 2,420,180, shows a similar process and specifies that it is for iron ore.
Also at the time of filing this application, applicant was familiar with the following U.S. patents: